Basic preparation is always the same.
First of all, take one of the balloons and inflate till desired dimension.
Then, take the paper and cut it to obtain strips of about half inch by one inch.
Take the glue and water down (same proportion in glue and water).
Stick the paper strips to the ballon with the glue, and cover totally the balloon.
Let dry and do that again another couple times.
Once you have covered the ballon with almost 3 layer of glue and paper, use the toilet paper (always in strips, same size
of newspaper strips).
When everything is dry, we'll get a ball (or whatever you have choosen) light but very resistant.
So, you have nothing to do but color and eventually varnish the ball.
In my creation, I have used acrylic colors and a water-based glossy varnish.
Cost
- I have found a bag of water bomb balloon for about 70 cents of €: since there were 100 ballons,
it's less than one cent/balloon

- Paper: you just need yesterday newspaper; with just one sheet you can cover 1 ballon
- Vinyl glue: I always buy a 1kg can, it's about 4 €
- Wadding/toilet paper: I have bought a big roll, 4 kg at about 7 €, and used it for 10 balls, and I think I can use it for at least 100 more balls
- acrylic: I use Pebeo, 5€ a 100ml pipe and 7€ a 250ml pipe
- water-based varnish, always Pebeo, about 7 €: it's about 3 years I use it and I still have to finish it